Pyogenic and tuberculous spondylodiskitis (vertebral osteomyelitis) in 80 adult patients.

Bacterial spondylodiskitis--i.e., adjacent vertebral osteomyelitis and diskitis--was studied in 80 adult patients. The infection was due to Mycobacterium tuberculosis in 31 cases (39%) and to pyogenic bacteria in 49 cases (61%). The latter pathogens included gram-negative bacilli in 16 cases (20%), Staphylococcus species in 15 (19%), Streptococcus species in 9 (11%), and Corynebacterium species in 1 (1%); the pathogens in the 8 remaining cases (10%) were not identified. Of the patients with tuberculous spondylodiskitis, 55% came from countries where tuberculosis is endemic (P < .001). Cases due to staphylococci and those due to M. tuberculosis were associated with a high frequency of previous active infection with those respective organisms at any site (47% and 42%, respectively; P < .001) and with a high rate of neurological complications (33% and 32%, respectively; P < .001). Nine patients with pyogenic spondylodiskitis (18%) but only one patient with tuberculous spondylodiskitis (3%) had diabetes mellitus (P < .05). Blood cultures were positive in 23 (56%) of the 41 cases of pyogenic spondylodiskitis due to an identified bacterium. Discovertebral needle biopsy contributed to the bacteriologic diagnosis in 29 (74%) of 39 cases.